The present invention relates to a novel method for the preparation of a derivative of 2,3-unsaturated alcohols or, more particularly, of a triorganosilylated 2,3-unsaturated alcohol useful as an intermediate reactant of various organic compounds such as medicines, perfumes and the like.
As is well known, various types of derivatives of 2,3-unsaturated alcohols are widely used in the synthetic preparation of organic compounds. These derivatives of 2,3-unsaturated alcohols are obtained with an oxirane compound as the starting material by several known methods. For example, an oxirane compound is reacted with a dialkylaluminum amide (see, for example, Journal of the American Chemical Society, volume 96 (1974), page 6513) or a dialkylboron trifluoromethanesulfonate (see, for example, Chemical Letters, 1977, page 1215) as the reactant. The method using these reactants is applicable to a trans-2,3-dialkyl-substituted oxirane compound but is not applicable to the cis isomers and other ordinary cyclic oxirane compounds due to the decreased reactivity.
Alternatively, there has been proposed a method in which lithium amide which is a strong basic compound is used as the reactant (see, for example, Journal of the American Chemical Society, volume 82 (1960), page 6370 and Organic Syntheses, volume 53 (1974), page 17). This method is, however, hardly applicable to those oxirane compounds having an organic group less resistant to the attack of the base or those oxirane compounds having a cyclic structure susceptible to rearrangement.
Further alternatively, sodium phenylselenide has been proposed as a relatively mild reactant to be reacted with an oxirane compound (see, for example, Journal of the American Chemical Society, volume 95 (1973), page 2697) but this method is industrially practiced only with great difficulties due to the toxicity of selenium.